Seeing Invisible Colors Knowing Neurons

Seeing Invisible Colors

What would the world be like without color?  Imagine you are a neurophysiologist, who studies color perception.  You know that light is a wave and that humans perceive color according to differential activation of color receptors, known as cones, in the retina.  You know that red cones are sensitive to long wavelengths, green cones are sensitive to medium wavelengths, and blue cones are sensitive to short wavelengths.  There’s just one issue: your entire life, you have been confined to a dark room where your only access to the outside world is a black and white television monitor.  You have never seen color.Continue reading

Understanding the Visual System: A Conversation with Botond Roska

Botond_RoskaWhen we see the world, there is a huge amount of processing that occurs in the neural circuits of the retina, thalamus, and cortex before we can even begin to comprehend our environment. And all of this computation happens very quickly! In this interview with Dr. Botond Roska, Senior Group Leader at the Friedrich Miescher Institute for Biomedical Research in Basel, Switzerland, we discuss his research on the elements of the visual system that compute visual information as well as how this knowledge can be used to help blind patients. Dr. Roska was inspired by the work and scientific approach of David Hubel (more about this on Wednesday!), and continues to follow his example: “Listen to the experiment, and not your colleagues,” says Dr. Roska. But what would he be, if not a neuroscientist? Find out in my conversation with Dr. Roska, who also shares his story of transition from musician, to medicine, to mathematics and to neuroscience!Continue reading

Retinal Prostheses: Restoring Vision to the Blind

Vision is arguably one of our most important senses.  We rely on it to recognize color, shape, movement, distance, and perspective about the world around us.   Although all parts of the eye help us perceive our environment, the most vital part is the retina, the thin layer of tissue that lines the back of the eye.  This structure contains several layers of cells interconnected by synapses.  When light enters through the eye, it passes all the way through the retina, until it is captured by photoreceptors.  These cells then convert the light energy into tiny electrochemical impulses, which are processed by retinal neurons, before the signal is sent to the brain.Continue reading